The invention relates to a process for deodorizing polluted air containing ill-smelling gaseous residues or organic origin, in which the air to be deodorized is treated with ozone and washed in a washing apparatus by means of an aqueous solution.
In numerous factories, such as for example knackers' yards, tallow-melting houses, waste-water treating plants, the presence of ill-smelling compounds in the gaseous effluents is an important cause of environmental problems. To remove these odours, numerous processes have already been proposed, such as oxidizing washing with multiple variants, adsorption over activated carbon, thermal oxidation at high temperature or catalytic oxidation at more moderate temperature, oxidation by ozone at ambient temperature possibly completed by a washing as in the process mentioned above. Most of these processes are not sufficiently efficient or are of prohibitive cost.
The main compounds responsible for nauseous odours are sulfurated compounds, particularly hydrogen sulfide, and mercaptans such as methyl mercaptan, ammonia and amines, such as trimethylamine, aldehydes such as acrolein, valeraldehyde, butyraldehyde, ketones, such as methylethylketone. Although most of the sulfurated and ammoniated compounds react with ozone, this does not apply to aldehydes.
It is an object of the invention to propose a process for neutralizing, in one treatment and at ambient temperature, the ill-smelling compounds, and more particularly those of the above-mentioned families, whether or not they are identified by analysis. It is a further object of the invention to propose a process which is highly efficient, easy to carry out, and consuming little oxidizing agent due to adjustment thereof as a function of needs.